Power module for an electric motor

ABSTRACT

A power module for an electric motor includes at least one semiconductor switch half bridge. The half bridge includes a high-side semiconductor switch and a low-side semiconductor switch. Each switch has a contact gap terminal formed by a surface region of the switch, in particular a flat surface region. The contact gap terminals, in particular a normal vector of the terminals, each points in a same direction. At least one electrically conductive layer is enclosed between the switches and electrically connects the contact gap terminal of the low-side semiconductor switch and the contact gap terminal of the high-side semiconductor switch of the half bridge to each other. Preferably an output terminal of the half bridge is formed by at least one electrically conductive layer.

This application is a 35 U.S.C. § 371 National Stage Application ofPCT/EP2016/074869, filed on Oct. 17, 2016, which claims the benefit ofpriority to Serial No. DE 10 2015 223 602.1, filed on Nov. 27, 2015 inGermany, the disclosures of which are incorporated herein by referencein their entirety.

BACKGROUND

The disclosure relates to a power module for an electric motor. Thepower module has at least one semiconductor switch half-bridge.

SUMMARY

According to the disclosure, the semiconductor switch half-bridge has ahigh-side semiconductor switch and a low-side semiconductor switch,wherein the semiconductor switches of the half-bridge have in each caseswitching path terminals formed by a surface region of the semiconductorswitch, said surface region being embodied in particular in a flatfashion. The switching path terminals, in particular a surface normalvector of the switching path terminal, in each case face in the samedirection. The high-side semiconductor switch and the low-sidesemiconductor switch enclose between one another at least oneelectrically conductive layer, which electrically connects a switchingpath terminal of the low-side semiconductor switch and a switching pathterminal of the high-side semiconductor switch of the half-bridge to oneanother. Preferably, an output terminal of the half-bridge is formed byat least one electrically conductive layer. A compact power module canadvantageously be provided by means of such a construction. The powermodule can thus be arranged in a space-saving manner in an electricmotor.

In one preferred embodiment of the power module, the switching pathterminal of the semiconductor switches of a half-bridge are situatedopposite one another. Preferably, the switching path terminals of asemiconductor switch are arranged in a coplanar manner with respect toone another. The switching path terminals connected to one another bymeans of the electrically conductive layer can thus enclose between oneanother the electrically conductive layer—in particular in the manner ofa sandwich. In this regard, the power module can advantageously beconstructed in a space-saving manner.

In one preferred embodiment, the power module is designed for polyphaseswitching, in particular switching of motor currents, and has at leastone or only one semiconductor switch half-bridge for each phase. Thepower module can thus have three semiconductor switch half-bridges forexample for driving a three-phase motor. Each semiconductor switchhalf-bridge can have for example a plurality or a multiplicity ofindividual semiconductor switch half-bridges which are connected inparallel with one another, in particular are arranged as a string.

The semiconductor switch half-bridge preferably has for each switchingpath terminal at least two, three or four, or more than four surfaceregions which are embodied as electrically conductive and are connectedto the switching path terminal. The surface regions can thus in eachcase form a contact pad.

In one preferred embodiment of the power module, the electricallyconductive layer has a phase busbar, onto which at least one contactfinger pointing away from the phase busbar transversely or with atransverse component is integrally formed in a flat extension of thelayer. The contact finger preferably connects to one another theswitching path terminals of the semiconductor switches that areconnected to the output terminal. The contact rail can thusadvantageously form a busbar which concentrates the currents led away bythe contact fingers or which distributes a current among the contactfingers, wherein the distributed current can be led to the switchingpath terminals by means of the contact fingers.

With further advantage, the busbar can project from a power moduleformed by a moulded module, for example, from a moulded body of themoulded module, and can thus be electrically contacted externally.

In one preferred embodiment, the semiconductor switches are formed ineach case by a field effect transistor, wherein that switching pathterminal of the high-side semiconductor switch which is connected to theoutput terminal of the half-bridge is a source terminal and thatswitching path terminal of the low-side semiconductor switch which isconnected to the output terminal of the half-bridge is a drain terminal.In this regard, a semiconductor switch half-bridge, formed from two MOSfield effect transistors (MOS=Metal Oxide Semiconductor), or MIS fieldeffect transistors (MIS=Metal Insulator Semiconductor), canadvantageously be constructed in a compact and space-saving manner. Withfurther advantage, the power module can have a low inherent inductanceas a result of the compact construction.

In one preferred embodiment, the semiconductor switches are formed ineach case by an IGBT (IGBT=Insulated Gate Bipolar Transistor), whereinthat switching path terminal of the high-side semiconductor switch whichis connected to the output terminal of the half-bridge is an emitterterminal and that switching path terminal of the low-side semiconductorswitch which is connected to the output terminal of the half-bridge is acollector terminal. The half-bridge can thus—consisting of IGBTtransistors—advantageously be constructed in a space-saving manner.

In one preferred embodiment, the contact finger comprises twoelectrically conductive layers which are arranged parallel to oneanother and which are separated from one another by an electricallyinsulating insulation layer. The layers of the contact finger preferablycontact mutually opposite terminals of mutually different semiconductorswitches. In this regard, advantageously, from the interspace extendingbetween the low-side semiconductor switch and the high-sidesemiconductor switch, the half-bridge, in particular the semiconductorswitches of the half-bridge, can be supplied with voltage in aspace-saving manner and with low inductance.

Preferably, the electrically insulating insulation layer is formed by adielectric. The dielectric is, for example, a polyimide layer or apolyamide layer. In this way, a link capacitor—corresponding to thesurface of the two electrically conductive layers which are arrangedparallel to one another—can advantageously be formed, which is thusintegrated in the power module.

In one preferred embodiment, the contact fingers of the phase busbar andof the busbar in each case intermesh. In this way, the feeding-in ofcurrent and the feeding-out of current from the power module can beembodied in a particularly compact fashion.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will now be described below on the basis of figures andfurther exemplary embodiments. Further advantageous embodiment variantsare evident from the features described in the dependent claims and inthe figures.

FIG. 1 shows—schematically—an exemplary embodiment of a semiconductorarrangement which forms a semiconductor switch half-bridge in which twosemiconductor switches enclose between one another electrical contactsfor feeding in current and feeding out current;

FIG. 2 shows—schematically in an exploded illustration—a semiconductorarrangement for forming three semiconductor switch half-bridges, formedfrom FET transistors, wherein electrical contacts for feeding in currentand feeding out current are enclosed between the low-side and high-sidetransistors;

FIG. 3 shows a production step for forming a power module comprising thecomponents illustrated in FIG. 2, wherein the high-side transistors aresoldered with electrical terminals, in particular a busbar and outputterminals;

FIG. 4 shows a production step for forming a power module comprising thecomponents illustrated in FIG. 3, wherein low-side semiconductorswitches are soldered with electrical terminals, in particular thebusbar and the output terminals;

FIG. 5 shows a further production step for forming a power modulecomprising the components illustrated in FIG. 4, wherein the componentsare embedded in moulding compound;

FIG. 6 shows a variant of the semiconductor arrangement illustrated inFIG. 4, in which the half-bridges are connected to a phase disconnectingswitch on the output side;

FIG. 7 shows a production step for producing a power module with phasedisconnecting switches, in which low-side semiconductor switches aresoldered onto electrical terminals;

FIG. 8 shows a production step for producing a power module with phasedisconnecting switches, in which the components shown in FIG. 7 areembedded in moulding compound.

DETAILED DESCRIPTION

FIG. 1 shows an exemplary embodiment of a semiconductor arrangement 1.In this exemplary embodiment, the semiconductor arrangement 1 forms apower module comprising a semiconductor switch half-bridge. In thisexemplary embodiment, the semiconductor switch half-bridge comprises alow-side semiconductor switch 2 and a high-side semiconductor switch 3.The low-side semiconductor switch 2, which is formed by a field effecttransistor in this exemplary embodiment, has a source terminal 7 asswitching path terminal and a drain terminal 5 as further switching pathterminal. The high-side semiconductor switch 3 has a drain terminal 6 asswitching path terminal and a source terminal 4 as further switchingpath terminal. The source terminal 4 of the high-side semiconductorswitch 3 is electrically connected to the drain terminal 5 of thelow-side semiconductor switch. The semiconductor switches 2 and 3 are ineach case embodied in a flat fashion. The source terminal 7 has asurface region 42 arranged opposite a surface region 43 of the drainterminal 6 of the high-side semiconductor switch 3. The source terminal7 and the drain terminal 5 of the low-side semiconductor switch 2 ineach case extend in a common plane.

The drain terminal 5 of the low-side semiconductor switch and the sourceterminal 4 of the high-side semiconductor switch 3 enclose between oneanother an output terminal 8 and in each case are electrically connectedto the output terminal 8 cohesively or by a material joint by means ofan electrical connection means 11. The connection means 11 is, forexample, a solder, a sintering solder connection or an electricallyconductive adhesive. In this exemplary embodiment, the output terminal 8is formed by a sheet-metal piece extending in a flat fashion orsheet-metal strips, also known as a lead frame. The output terminal 8 isformed by copper or silver sheet metal, for example. The output terminal8 can be formed by a contact finger, for example.

In this exemplary embodiment, the source terminal 7 is connected to anelectrically conductive layer 9 by means of a connection means 11, inparticular solder, electrically conductive adhesive or sintering metal.The electrically conductive layer 9 can form for example an outputterminal for supplying the semiconductor switch half-bridge withcurrent. The drain terminal 6 is connected to an electrically conductivelayer 10 by means of a connection means 11, in particular solder orelectrically conductive adhesive or sintering metal. In this exemplaryembodiment, the electrically conductive layer 10 forms a furtherterminal for supplying the semiconductor switch half-bridge withcurrent. In this exemplary embodiment, the electrically conductivelayers 9 and 10 are arranged parallel and at a distance from one anotherand enclose between one another an electrically insulating layer 12. Theelectrically conductive layers 9 and 10 are thus electrically insulatedfrom one another.

The source terminal 7 and the drain terminal 6 thus enclose between oneanother the electrically conductive layers 9 and 10 and the electricallyinsulating layer 12—enclosed between the electrically conductive layers9 and 10 in the manner of a sandwich. The surface region of the sourceterminal 7 is thus electrically contacted by the electrically conductivelayer 9 and the surface region 43 of the drain terminal 6 iselectrically contacted by the electrically conductive layer 10. Theelectrically conductive layers 9 and 10 are led toward the outside, forexample, such that the semiconductor switch can thus be electricallycontacted externally.

The semiconductor switch half-bridge thus formed, which is constructedin a compact fashion, can be embedded into a moulded body 15. The outputterminal 8, embodied for example as an electrically conductive layer,projects from the moulded body 15 in this exemplary embodiment. Theelectrically conductive layer 9, the electrically conductive layer 10and the insulation layer 12 enclosed therebetween together can form abusbar 44 or part of a busbar and project jointly from the moulded body15. The semiconductor switch half-bridge can thus be supplied withcurrent via the busbar 44, wherein the current—switched by the low-sidesemiconductor switch 2 and the high-side semiconductor switch 3—can flowaway via the output terminal 8.

The low-side semiconductor switch 2 has an outwardly facing insulationlayer 13, via which heat loss generated in the semiconductor switch 2can be dissipated. The high-side semiconductor switch 3 has an outwardlyfacing insulation layer 14, via which heat loss generated in thesemiconductor switch 2 can be dissipated. Heat dissipation from thehalf-bridge comprising the semiconductor switches 2 and 3 can thusadvantageously be effected via two sides facing away from one another.The insulation layers 13 and 14 can be formed in each case by a ceramiclayer, DBC layer (DBC=Direct Bonded Copper), in which a copper layer forcohesive connection, in particular soldering or sintering, to a heatsink faces outward. A heat sink, for example a cooling body, can becoupled to the insulation layers 13 and 14, which are formed by apolyimide layer, for example, by means of a thermally conductiveadhesive.

FIG. 2 shows—schematically—parts of a semiconductor arrangement 16, inan exploded illustration. In this exemplary embodiment, thesemiconductor arrangement 16 forms a power module having threesemiconductor switch half-bridges for driving a three-phase electricmotor or a three-phase electric machine. In this exemplary embodiment,the semiconductor arrangement 16 comprises three high-side semiconductorswitches, namely a high-side field effect transistor 17, a high-sidefield effect transistor 18 and a high-side field effect transistor 19.The field effect transistors 17, 18 and 19 are in each case embodied ina flat fashion, wherein the switching path terminals, in particular adrain terminal 23 and a source terminal 25, in each case face—with theirflat extension—in the same direction.

The drain terminal 23 of the semiconductor switch 17 is also formed bytwo further terminal parts 23 a and 23 b. The source terminal of thesemiconductor switch 17 also comprises, besides the source terminal 25,two further terminal parts 25 a and 25 b, which are formed in each caseby a surface region of the semiconductor switch 17.

The surface regions which form the source terminal and the drainterminal of the semiconductor switch 17 alternate along a longitudinalaxis 30 alternately with one another. In this regard, along thelongitudinal axis 30, the surface region which forms the source terminal25 is arranged adjacently to the surface region which forms the drainterminal 23. The surface region which forms the source terminal 25 isfollowed by the surface region which forms the drain terminal part 23 a.Along the longitudinal axis, the drain terminal part 23 a is followed bythe source terminal part 25 a, and the source terminal part 25 a isfollowed by the drain terminal part 23 b. The drain terminal part 23 bis followed by the source terminal part 25 b. In this regard, two sourceterminal parts arranged along the longitudinal axis 30 enclose a drainterminal part between one another, and drain terminal parts arrangedalong the longitudinal axis 30 enclose a source terminal part betweenone another.

The semiconductor arrangement 16 also comprises a busbar which, in thisexemplary embodiment, comprises two electrically conductive layers 28and 31 which are arranged parallel to one another and are electricallyisolated from one another by means of an insulation layer 29. The busbar27 extends along the longitudinal axis 30. Contact fingers such as thecontact finger 32 are integrally formed onto the busbar 27 at a distancefrom one another along the longitudinal axis 30, wherein the contactfingers respectively—like the busbar 27—comprise the electricallyconductive layers 28 and 31 and the insulation layer 29 arrangedtherebetween. The busbar and the contact fingers integrally formed ontothe busbar 27 thus comprise two contact planes which are arrangedparallel to one another and are electrically isolated from one anotherby means of the insulation layer 29.

The electrically conductive layer 31 of the contact finger 32 isdesigned to be soldered with the drain terminal 23. In this exemplaryembodiment, two further contact fingers 32 a and 32 b spaced apart fromone another along the longitudinal axis 30 are also integrally formedonto the busbar 27. The electrically conductive layer 31 of the contactfinger 32 a is designed to be electrically connected, in particularsoldered, for example reflow-soldered, to the drain terminal 23 a. Theelectrically conductive layer 31 of the contact finger 32 b is designedto be soldered to the drain terminal 23 b. The busbar 27, in particularthe electrically conductive layer 31 of the busbar 27, can thus beelectrically connected to the drain terminal, in particular the drainterminal parts 23, 23 a and 23 b, of the semiconductor switch 17 bymeans of the contact fingers 32, 32 a and 32 b. The semiconductor switch17 can thus be electrically connected to an electrical voltage source,in particular a positive pole of the voltage source, by means of thebusbar 27.

The semiconductor arrangement 16 also comprises a low-side semiconductorswitch 20, which is designed to form a semiconductor switch half-bridgetogether with the high-side semiconductor switch 17. The semiconductorarrangement 16 also comprises a semiconductor switch 21 designed to forma semiconductor switch half-bridge together with the high-sidesemiconductor switch 18, and a further low-side semiconductor switch 22designed to form a semiconductor switch half-bridge together with thehigh-side semiconductor switch 19.

The semiconductor arrangement 16 also comprises an output terminal 34,which in this exemplary embodiment is embodied as—for example stamped orlaser-cut—sheet-metal piece, also known as a lead frame. The outputterminal 34 comprises a busbar extending along the longitudinal axis 30and contact fingers 33, 33 a and 33 b integrally formed onto the busbarat a distance from one another along the longitudinal axis 30.

The contact finger 33 is designed to be soldered by a flat side to thesource terminal 25 of the high-side semiconductor switch 17 and to besoldered by an opposite side relative thereto to a drain terminal 24 ofthe low-side semiconductor switch 20. A source terminal 26 of thelow-side semiconductor switch 20, said source terminal being arrangedadjacently to the drain terminal 24 along the longitudinal axis 30, isdesigned to be soldered to the electrically conductive layer 28 of thecontact finger 32, such that the source terminal 26 can be connected toa pole of a voltage source, in particular the negative pole of thevoltage source, via the busbar 27, in particular the electricallyconductive layer 28 of the busbar 27.

The contact finger 33 a is designed to be soldered to the sourceterminal 25 a, and the contact finger 33 b is designed to be connectedto the source terminal 25 b.

The contact finger 33 of the output terminal 34 thus connects the sourceterminal 25 of the high-side semiconductor switch 17 to the drainterminal 24 of the low-side semiconductor switch 20 and a partialterminal 24 a of the drain terminal 24 to the partial terminal 25 a ofthe source terminal 25. The contact finger 33 b connects the partialterminal 24 b of the drain terminal of the low-side semiconductor switch20 to the partial terminal 25 b of the source terminal 25 of thehigh-side semiconductor switch 17. The contact fingers 33, 33 a and 33 bof the output terminal 34 are thus enclosed—in the manner of asandwich—between the semiconductor switches each extending in a flatfashion, namely the high-side semiconductor switch 17 and the low-sidesemiconductor switch 20.

Still further contact fingers for electrically contacting the high-sidesemiconductor switch 18 and another three further contact fingers forelectrically contacting the high-side semiconductor switch 19 areintegrally formed onto the busbar 27.

The semiconductor arrangement 16 also comprises an output terminal 35for the semiconductor switch half-bridge, comprising the high-sidesemiconductor switch 18 and the low-side semiconductor switch 21, and anoutput terminal 36 for the half-bridge, comprising the high-sidesemiconductor switch 19 and the low-side semiconductor switch 22. Thus aphase of an electric machine, in particular a stator coil of theelectric machine, can be respectively connected to the output terminals34, 35 and 36.

The contact fingers of the busbar 27 and the contact fingers of theoutput terminal, such as the output terminal 34, 35 or 36, are in eachcase designed to intermesh in a flat extension. The contact fingers ofthe busbar and of the output terminal are thus arranged in a commonplane and can be enclosed jointly between the high-side semiconductorswitch 17 and the low-side semiconductor switch 20—in particular in themanner of a sandwich.

In another embodiment, the semiconductor switches 17, 18, 19, 20, 21 and22 may be embodied in each case as an IGBT. The source terminal thencorresponds to an emitter terminal, and the drain terminal correspondsto a collector terminal.

The semiconductor switches have in each case a—not illustrated in FIG.2—control terminal, in particular gate terminal, and are in each casedesigned to receive a control signal for turning on the semiconductorswitch at the gate terminal and to turn on or to turn off thesemiconductor switch depending on the control signal. The gate terminalcan be formed for example by an insulated region of the busbar 27.

FIG. 3 shows a production step for producing a power module, comprisingthe parts already illustrated in FIG. 2 for the semiconductorarrangement 16 illustrated in FIG. 2. In the production step illustratedin FIG. 3 the contact fingers of the busbar 27 are placed with theelectrically conductive layer 31 onto the switching path terminals ofthe high-side semiconductor switches such as the semiconductor switch17, the semiconductor switch 18 and the semiconductor switch 19 and areelectrically and cohesively connected—for example by means of a solderpaste and reflow soldering. The contact fingers of the output terminal34 are placed onto the corresponding switching path terminals—as alreadydescribed in FIG. 2—of the high-side semiconductor switch 17 and aresoldered to the corresponding switching path terminals by a solderpaste—as described in FIG. 1.

In the same step as illustrated in FIG. 3, the output terminal 35 can besoldered to the high-side semiconductor switch 18 and the outputterminal 36 can be soldered to the high-side semiconductor switch 19.

FIG. 4 shows a production step for producing the power module comprisingthe components illustrated in FIG. 2, in which the low-sidesemiconductor switches 20, 21 and are placed onto the busbar 27 and ontothe output terminals 34, 35 and 36 and are soldered to the busbar 27 andthe output terminals.

The output terminal 34 thus connects the source terminal of thehigh-side semiconductor switch 17 to the drain terminal of the low-sidesemiconductor switch 20. The semiconductor switch half-bridgescomprising the semiconductor switches arranged in parallel with respectto one another in accordance with FIG. 4, namely the high-sidesemiconductor switch 17 and the low-side semiconductor switch 20, whichjointly form a semiconductor switch half-bridge, can thus be connectedto an electrical voltage source by means of the busbar 27.

FIG. 5 shows a production step for producing the power module, in whichmoulding compound is used to mould around the semiconductor arrangementshown in FIG. 4 in such a way that the busbar 27 and the outputterminals 34, 35 and 36 project from the moulded body 15 formed bythe—in particular fully polymerized—moulding compound.

FIG. 5 also shows a variant in which the power module is thermallyconductively connected to a heat sink, a cooling body 45 in thisexample. The insulation layer 13 is thermally conductively contacted bythe cooling body, in particular cooling plate, such that heat loss canbe dissipated by the cooling body 45. The cooling body 45 can forexample be connected to a heat pipe, or itself be formed by a heat pipe.

FIG. 6 shows a variant of the semiconductor arrangement illustrated inFIGS. 2, 3 and 4, in which the semiconductor switch half-bridges are ineach case connected to a phase disconnecting switch on the output side.In this exemplary embodiment, the phase disconnecting switch is formedby a field effect transistor, in particular corresponding to thehigh-side semiconductor switch 17.

The high-side semiconductor switches such as the semiconductor switch17, 18 and 19 are in each case arranged with their flat extension in thesame plane as the phase disconnecting switches, namely a phasedisconnecting switch 38 connected to the output of the high-sidesemiconductor switch 17 on the input side, a phase disconnecting switch39 connected, on the input side, to the half-bridge comprising thehigh-side semiconductor switch 18, and a phase disconnecting switchconnected, on the input side, to the output of the half-bridgecomprising the high-side semiconductor switch 19 and the low-sidesemiconductor switch 22.

The semiconductor arrangement 16 comprises an electrically conductiveconnection element 37 for the purpose of connecting the phasedisconnecting switch 38 to the high-side semiconductor switch 17, saidconnection element being embodied as longitudinally extending contactfingers in this exemplary embodiment.

The connection element 37 is formed for example as in particular stampedor laser-cut sheet metal, in particular copper sheet, and engages by anend section between the contact fingers 32 and 32 a of the busbar 27 andcan thus electrically contact the source terminal 25 between the contactfingers 32 and 32 a. The connection element 37 thus contacts the sourceterminal 25 instead of the contact finger 33—in the semiconductorarrangement 16 in FIG. 2. An end section of the connection element 37 isconnected to a switching path terminal of the phase disconnecting switch38 by soldering, such that the source terminal 25 of the semiconductorswitch 17, which together with the drain terminal 24 of the low-sidesemiconductor switch 20 forms the already mentioned output of thesemiconductor switch half-bridge, is connected to the phasedisconnecting switch 38.

The semiconductor arrangement 16 also comprises the output terminal 34,which is connected to a switching path terminal of the phasedisconnecting switch 38 in the semiconductor arrangement 16.

The semiconductor arrangement 16 also comprises a connection element 37a, which extends with an end section between the contact finger 32 a andthe contact finger 32 b, and a further connection element 37 b, whichextends in a manner arranged adjacently to the contact finger 32 b. Theconnection elements 37, 37 a and 37 b thus form an output of thesemiconductor switch half-bridge comprising the high-side semiconductorswitch 17 and the low-side semiconductor switch 20 and connect saidsemiconductor switch half-bridge to the phase disconnecting switch 38.The busbar 27 and the connection elements such as the connection element37 and the output terminals 34, 35 and 36 are in each case arranged in acommon plane.

FIG. 7 shows a further production step for producing the power module,comprising the semiconductor arrangement 16, in which in FIG. 7 thelow-side semiconductor switch 20 is arranged opposite the high-sidesemiconductor switch 17, the low-side semiconductor switch 21 isarranged opposite the high-side semiconductor switch 18, and thelow-side semiconductor switch 22 is arranged opposite the high-sidesemiconductor switch 19. The low-side semiconductor switches 20, 21 and22 are supplied with voltage in each case via the busbar 27, inparticular the electrically conductive layer 28, wherein the drainterminals as output terminal are electrically connected to theconnection elements such as the connection element 37. The low-sidesemiconductor switches 20, 21 and 22 can in each case be soldered to thebusbar 27 and to the connection element such as the connection element37 by means of reflow soldering.

FIG. 8 shows the power module in which the semiconductor arrangement 17shown in FIG. 7 is embedded by means of a moulding compound in such away that the busbar 27 and the output terminals 34, 35 and 36 projectfrom a moulded body 41 formed by the moulding compound.

The invention claimed is:
 1. A power module for an electric motor,comprising: at least one semiconductor switch half-bridge including: aplurality of semiconductor switches; an output terminal; and at leastone electrically conductive layer, wherein: the plurality of switchesincludes a high-side semiconductor switch and a low-side semiconductorswitch; each semiconductor switch has a respective switching pathterminal formed by a respective flat surface region of the semiconductorswitch; the switching path terminal of each semiconductor switch facesin a same direction; the at least one electrically conductive layer isenclosed between the high-side semiconductor switch and the low-sidesemiconductor switch, and electrically connects the respective switchingpath terminal of the low-side semiconductor switch and the respectiveswitching path terminal of the high-side semiconductor switch of thehalf-bridge to each other; and the output terminal of the half-bridge isformed by the at least one electrically conductive layer.
 2. The powermodule according to claim 1, wherein the respective switching pathterminals of the plurality of semiconductor switches of a half-bridgeare arranged so as to be opposite one another.
 3. The power moduleaccording to claim 1, wherein the power module is configured to enablepolyphase switching and has at least one or only one semiconductorswitch half-bridge assigned to each phase.
 4. The power module accordingto claim 1, wherein: the at least one electrically conductive layer has:a phase busbar; and at least one contact finger integrally formed in aflat extension of the at least one electrically conductive layer ontothe phase busbar, the at least one contact finger points away from thephase busbar transversely or has a transverse component; and the atleast one contact finger connects to each other the respective switchingpath terminals of a subset of the plurality of semiconductor switchesthat are connected to the output terminal.
 5. The power module accordingto claim 1, wherein: each of the plurality of semiconductor switches isformed by a respective field effect transistor; the respective switchingpath terminal of the high-side semiconductor switch is connected to theoutput terminal of the half-bridge, and is a source terminal; and therespective switching path terminal of the low-side semiconductor switchis connected to the output terminal of the half-bridge, and is a drainterminal.
 6. The power module according to claim 1, wherein: each of theplurality of semiconductor switches is formed by a respective insulatedgate bipolar transistor; the respective switching path terminal of thehigh-side semiconductor switch is connected to the output terminal ofthe half-bridge, and is an emitter terminal; and the respectiveswitching path terminal of the low-side semiconductor switch isconnected to the output terminal of the half-bridge, and is a collectorterminal.
 7. The power module according to claim 1, further comprising:a busbar; and at least one contact finger integrally formed onto thebusbar, wherein the at least one contact finger electrically contacts arespective switching path terminal configured to supply power to thehalf-bridge.
 8. The power module according to claim 7, wherein: the atleast one contact finger has a plurality of layers that includes: anelectrically insulating insulation layer; and two electricallyconductive layers arranged parallel to each other and separated fromeach other by the electrically insulating insulation layer; wherein theplurality of layers of the at least one contact finger contact mutuallyopposite terminals of mutually different semiconductor switches of theplurality of semiconductor switches.
 9. The power module according toclaim 7, wherein: the at least one electrically conductive layer has: aphase busbar; and at least one further contact finger integrally formedin a flat extension of the at least one electrically conductive layeronto the phase busbar; the at least one further contact finger pointsaway from the phase busbar transversely or has a transverse component;the at least one further contact finger connects to each other therespective switching path terminals of a subset of the plurality ofsemiconductor switches that are connected to the output terminal; the atleast one contact finger of the busbar and the at least one furthercontact finger of the phase busbar and of the output terminal in eachcase intermesh.
 10. The power module according to claim 1, wherein thepower module is embedded into a moulded body.
 11. The power moduleaccording to claim 8, wherein the electrically insulating layer includesa dielectric.